Acid-catalyzed decomposition alcohol

Turner JO. The acid-catalyzed decomposition of aliphatic hydroperoxides reactions in the presence of alcohols. Tetrahedron Lett 1971 14 887-890. 

This decomposition can be accounted for the base-catalyzed hydrolysis. At pH values below four, the acid-catalyzed decomposition that causes acceleration in hydrolysis is obser ed due to dehydration of the alcoholic portion of the... 

The products from cumene hydroperoxide decomposition induced by organic sulfur compounds were determined by quantitative NMR except for phenol by high-pressure liquid chromatography and cumene hydroperoxide by iodometric titration (16). Cumyl alcohol is produced in the initial oxidation of sulfenic acid to sulfonic acid, and subsequently most of it is converted to a-methylstyrene as shown in Table II. The major products (40-45%) are phenol and acetone consistent with an acid-catalyzed decomposition of cumene hydroperoxide. Considerable... 

As an alternative to landfilling or high-temperature incineration, the acid-catalyzed decomposition in alcohol efficiently and safely converts the composite materials to alkyl levulinate at moderate temperatures. The product composition obtained by heating particle board chips in ethanol with sulforic acid catalyst for 30 min at 200°C was similar to that obtained from ordinary wood treatment. The charcoal product was removed by filtration the ethanol, water, and ethyl formate product flash-distilled and the ester levulinate separated from the resinous product by extraction into diethyl ether. In this case, the resinous products also contained the UF binding resins that were initially present in the waste board. The UF resin-derived components were intimately mixed with or chemically attached to the lignin resin there was no way to extract and separate the lignin from the UF component. 

Reactions of Vinyl Ethers. Vinyl ethers undergo the typical reactions of activated carbon—carbon double bonds. A key reaction of VEs is acid-catalyzed hydrolysis to the corresponding alcohol and acetaldehyde, ie, addition of water followed by decomposition of the hemiacetal. Eor example, for MVE, the reaction is... 

Another example of a transannular cyclization that occurs in the solid state is provided by the epoxy alcohol 31. This compound is stable when dissolved in organic solvents and in 0.25N sulfuric acid. However, the crystals transform rapidly to 32. Although the process is accompanied by partial melting, it appears to be a true solid-state one. Interestingly, the reaction is slowed down appreciably when the dry crystals are covered with ether. Hydrogen bromide is eliminated in the reaction and it may be that an acid-catalyzed process is also occurring in the presence of solvent this process may be slowed down by the dissolution of the decomposition products in the solvent (77). 

In oxidation studies it has usually been assumed that thermal decomposition of alkyl hydroperoxides leads to the formation of alcohols. However, carbonyl-forming eliminations of hydroperoxides, usually under the influence of base, are well known. Of more interest, nucleophlic rearrangements, generally acid-catalyzed, have been shown to produce a mixture of carbonyl and alcohol products by fission of the molecule (6). For l-butene-3-hydroperoxide it might have been expected that a rearrangement (Reaction 1) similar to that which occurs with cumene hydroperoxide could produce two molecules of acetaldehyde. 

In contrast, the acid-catalyzed hydrolysis of alkyl selenates is A-2158. The actual species which undergoes decomposition to alcohol and sulfur trioxide is probably the zwitterion as in the case of phosphate monoester monoanions. Evidence for sulfur trioxide as the reactive initial product of the A-1 solvolysis is obtained from the product compositions arising with mixed alcohol-water solvents. The product distribution is identical to that found for sulfur trioxide solvolysis, with the latter exhibiting a three-fold selectivity for methanol. Although the above entropies of activation and solvent deuterium isotope effects do not distinguish between the conventional A-l mechanism and one involving rate-limiting proton transfer, a simple calculation, based on the pKa of the sulfate moiety and the fact that its deprotonation is diffusion controlled. 

Condensed-Phase Mechanisms. The mode of action of phosphorus-based flame retardants in cellulnsic sy stems is probably best understood. Cellulose decomposes by a noncalalyzed route lo tarry depolymerization products, notably levoglucosan, which then decomposes to volatile combustible fragments such as alcohols, aldehydes, ketones, and hydrocarbons. However, when catalyzed by acids, the decomposition of cellulose proceeds primarily as an endothermic dehydration of the carbohydrate to water vapor and char. Phosphoric acid is particularly efficaceous in this catalytic role because of its low volatility (see Phosphoric Acids and Phosphales). Also, when strongly heated, phosphoric acid yields polyphosphoric acid which is even more effective in catalyzing the cellulose dehydration reaction. The flame-retardanl action is believed to proceed by way of initial phosphory lation of the cellulose. 

Alcohols can undergo acid-catalyzed dehydration to give either the corresponding alkenes or the corresponding ethers. The product distribution of the dehydration of alcohols over Nafion-H catalyst shows temperature dependence187 (Table 5.40). Alcohols are thus efficiently dehydrated in the gas phase over Nafion-H under relatively mild conditions with no evidence for any side reactions such as dehydrogenation or decomposition. At higher temperature, olefin formation predominates. 

The reaction typically gives 60% to 70% of the maximum yield. The reaction is a reversible process. An ester reacting with water, giving the carboxylic acid and alcohol, is called hydrolysis it is acid catalyzed. The base-promoted decomposition of esters yields an alcohol and a salt of the carboxylic acid this process is called saponification. 

Acetaldehyde decomposition, reaction pathway control, 14-15 Acetylene, continuous catalytic conversion over metal-modified shape-selective zeolite catalyst, 355-370 Acid-catalyzed shape selectivity in zeolites primary shape selectivity, 209-211 secondary shape selectivity, 211-213 Acid molecular sieves, reactions of m-diisopropylbenzene, 222-230 Activation of C-H, C-C, and C-0 bonds of oxygenates on Rh(l 11) bond-activation sequences, 350-353 divergence of alcohol and aldehyde decarbonylation pathways, 347-351 experimental procedure, 347 Additives, selectivity, 7,8r Adsorption of benzene on NaX and NaY zeolites, homogeneous, See Homogeneous adsorption of benzene on NaX and NaY zeolites... 

Flammable Liquid, Corrosive, Poison SAFETY PROFILE A poison by skin contact and ingestion. Moderately toxic by inhalation. Ingestion of even small amounts can be fatal. A skin and severe eye irritant. Inhalation of a small amount can cause immediate lachrymation, coughing, choking, and respiratory distress. Death may result from pulmonar) edema which may not appear for several hours after exposure. A dangerous fire and moderate explosion hazard when exposed to heat, spark, or flame. Self-reactive. Iron salts may catalyze a potentially explosive thermal decomposition. Incompatible with water, iron, metal salts, acids, alkalies, amines, alcohols. Stable under refrigeration below 20°, but one reference (1973) reports that it has exploded while stored in a refrigerator. Present-day formulations appear to be more stable. Temperatures above 20° can cause decomposition. When heated to decomposition it emits acrid smoke and fumes. 

A mechanistic study of the role of the lanthanide cations suggests that they catalyze decomposition of borohydride by the hydroxylic solvent to afford alkoxyborohydrides, which may responsible for the observed regioselectivity. The stereoselectivity of the process is also modified by the presence of Ln " ions, in that axial attack of cyclohexenone systems is enhanced. a,p-Unsaturated aldehydes are regio-selectively reduced to allylic alcohols by bis(triphenylphosphine)copper(I) tetrahydroborate in the presence of Lewis acid catalyst. ... 

Copper-catalyzed decomposition of the diazonium chloride 53, derived from the appropriate amine, gave the spiro compound 54 besides a few percent of the phenylpyrrole 55. The phenylpyrrole 55 was obtained in high yield from the diazonium chloride 53 or from the spiro compound 54 on heating in hydrochloric acid. If the spiro derivative 54 was melted at 200°C or heated in 100% phosphoric acid or 60% sulfuric acid at 100°C, the pyrrolo[l,2-c]quinazoline 57 was formed, whereas in alcoholic solution, in the presence of a few drops of concentrated sulfuric acid, compound 56 was obtained. 

II. Unimolecular Acid-Catalyzed Reactions Involving Acyl-Oxygen Fission. At least one instance is known in which decomposition of the protonated complex does not seem to depend upon the attack of water or an alcohol molecule. It is the formation or hydrolysis of esters of 2,4,6-trimethylbenzoic acid in sulfuric acid solution. Since cryoscopic studies have shown that the acid gives a molar freezing point depression of four (p. 39), and the ester five (p. 225), we must conclude that decomposition of the protonated complex to the acyl carbonium ion 0... 

This reaction has been modified from acid-catalyzed cyclization of uredo acids from palladium catalyzed MCR among aldehydes, carbon monoxide, and ureas and from Ugi five-component condensation. Alternatively, hydantoins can also be synthesized via other methods, such as the 1,3-Dipolar Cycloaddition of l-oxa-4-azabutadiene and aryl isocyanates and the decomposition of barbituric acids in alcohol. ... 

This fact illustrates the point where the functions of metal salt catalysts become apparent. If oxidation to the alcohol, ketone or carboxylic acid (i.e. beyond the hydroperoxide stage) is the objective, metal catalysts should be used to promote decomposition of the hydroperoxide. The metal ion (complex) catalyzed decomposition of hydroperoxides is responsible for the sustained and rapid formation of radicals participating in a chain reaction. The most effective are metals with at least two accessible oxidation states. Both components of a redox couple may be capable of reacting with alkyl hydroperoxides ... 

Well known examples are oxidations with Mn04 where the latter is transferred into an apolar organic medium such as benzene, purple benzene , by complexed macrocyclic polyethers or quaternary cations, both in liquid-liquid and solid-liquid phase-transfer systems This procedure eliminates the self-catalyzed decomposition of Mn04 which occurs with evolution of O2. Olefins, alcohols, alkylated arenes, etc. are thus oxidized to carboxylic acids, ketones, aldehydes, or glycols. 

The novel partially crystalline polymer (3) with munber-average molecular weight (M ) of up to 5700 was prepared imder various conditions by catalyzed self-condensation of 3-hydroxypropyl methoxycarbonylethyl sulfide (4) or 3-hydrox5 ropyl carboxyethyl sulfide (5) (22). The degree of crystallinity, melting temperature (Tm and temperature of initial decomposition (Ta) were 36-46%, 37-47°C, —61 to —70°C, and 164-260°C, respectively. The monomers (4) and (5) were prepared by an addition of methyl 3-mercaptopropionate and 3-mercaptopropionic acid with allyl alcohol [107-18-6] catalyzed by AIBN [2,2 -azobis(2-methylpropionitrile), azobisisobutyronitrile, azodiisobutyro-dinitrile, 2,2 -azobis(2-methylpropanenitrile), a,a -azodiisobutyronitrile, 2,2 -azo-bis(isobut5T onitrile), 2,2 -dicyano-2,2 -azopropane, Porofor-57, 2,2 -dimethyl-2,2 -azodipropionitrile, 2,2(-azobis(2-methylpropionitrile))] [78-67-1]. 

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